Re: XML storing and management

On 27 sep, 22:52, Bob Badour <bbad..._at_pei.sympatico.ca> wrote:
> Jan Hidders wrote:> > On 27 sep, 19:07, Bob Badour <bbad..._at_pei.sympatico.ca> wrote:>> >>Jan Hidders wrote:>> >>>On 27 sep, 16:27, Bob Badour <bbad..._at_pei.sympatico.ca> wrote:>> >>>>Jan Hidders wrote:>> >>>>>On 27 sep, 02:19, JOG <j..._at_cs.nott.ac.uk> wrote:>> >>>>>>Ok, so why is it exactly cdt, despite the inherent flaws of a> >>>>>>hierarchical model such as XML, it has seen such widespread uptake?>> >>>>>It's all hype, of course.>> >>>>>Btw., what fundamental flaws?>> >>>>Well, let's see... How about we start with: "The inability to re-order> >>>>the data without changing meaning and without destroying information." ?>> >>>"Hierarchical models such as XML" are not necessarily ordered-only> >>>data models. In fact most proposals for semistructured data models> >>>before XML weren't.>> >>>But even in XML this is not a big problem. Whether reordering destroys> >>>information or not depends on your interpretation of the data. If you> >>>send me an XML document and in addition tell me that certain parts> >>>represent sets then I can reorder them without destroying any> >>>information. The fact that XML is an ordered data model only implies> >>>that it *might* destroy informaton, not that it *must*.>> >>That's a nit. If one cannot always safely reorder, then one cannot> >>safely reorder.>> > I thought we were having a serious discussion, not playing trivial> > word games. My mistake.>> I am having a serious discussion. I am not the one picking at nits.

I disagree. I think you are.

> What your position boils down to is: XML is needlessly complex.

Not really. What I said is that concerning the aspect we were
discussing it is actually missing a construct. So my position is more
accurately described as that it is "too simple", not "too complex".

> As a> result of the needless complexity, one cannot re-order the data without> changing meaning and without destroying information.

That is too imprecise to be correct. You can in some sense always
reorder if you want to. What I said is that whether this loses
information or not is a matter of interpretation. Note by the way that
this is also true for the Relational Model: you cannot always
arbitrarily permute the atomic values in a relation without risking
changing its meaning. Also there it is a matter of interpretation
whether this is actually a problem or not.

> BUT if we add even> more complexity, we can sometimes re-order data. Sometimes.